Improvement in the manufacture of iron



2 Sheets-Sheet 1.

1. YATES.

Manufacture of Iron.

N. PETERS. FIwYo-UOImgmpIwI. Washington D. C.

Patented March 1, 1864.`

J. YATES.

Manufacture of Iron.

2 Sheets-Sheet 2t No. 41,805. y Patented March 1, 1864.

Invwaay' JWM UNITED STATES PATENT EEICE9 JOSEPH YATES, OF MO'ITv HAVEN, NEV YORK.

IMPROVEMENT IN THE MANUFACTURE OF IRON.

Specification forming part of Letters Patent No. 4|,805, dated March l, 1864.

To all whom it may concern:

Be it known that I, JosErn Yarns, of Mott Haven, in the county of Westchester and State of New York, have invented certain new and useful Improvements in the Manufacture of Malleable or W'rought Iron, and I hereby declare that the following, taken in connection with the accompanying drawings, is such a full, clear, and exact description of the same, as will enable others skilled in the art to make and use the same.

My invention relates to the manufacture of iron by a direct process-that is to say, to the production of malleable or wrought iron directly from the ore. Furnaces or apparatuses for this purpose constructed or devised prior to this my invention were seriously defective, from the fact that the parts constituting such furnaces or apparatuses did not bear that relation to each other without which continuity and regularity of operation-the elements so essential to successful manufacture-could not be attained.

.The present vimprovements have for their obj ect the combination and arrangement of those parts of an apparatus or furnace for making malleable iron direct from the ore in which the ore is reduced, so that the operation therein effected may be carried Von uninterruptedly in regular succession with greater uniformity throughout the whole apparatus at a greater saving of fuel, and with increased yield of metal, than this could ever be attained heretofore.

rIo this effect my invention consists, rst, in the method, hereinafter described, of equalizing the temperature throughout all the chambers of the reducing-oven by increasing the capacity of said chambers in proportion to the intensity of the heat of the flame passing through them, secondly, in the method, hereinafter described, of equalizing the temperature throughout all the chambers of the reducing oven by proportioning the area of the iiues leading to and from the chambers in accordance with the intensity of the heat of the I flame passing through said flue andchamber, thirdly, in the method, hereinafter described, of equalizing the temperature throughout all the chambers of the reducing-oven by so combining said chambers with iiues thatv the capacity of the former and the area of the latter are proportionate to the intensity of the heat of the iiame.

In order to elucidate the principles of my invention, I shall briefly refer to the general construction, arrangement, and operation of the apparatus to which my improvement is applied.

The apparatus embodying my invention represented in sectional elevations according to the lines A B and C D in Figures 1 and 2, respectively, is composed of a reducing-oven, O, to which my present invention is particularly applied, of a chimney or stack, S, and of a welding-furnace, W. 'Phereducing-oven O is a quadrangular structure erected on castiron columns at such height from the ground or base of the welding-furnace so that the latter, with the exception of the flues connecting it with the reducing-oven, shall be completely isolated, and also so that free access may be had thereto from all sides. Four columns, E,

having girders F and arches G thrown from one -to another, support the outer shell or structure of the oven, which is built of firebrick, and strongly bound in by a net of castiron ribs or braces and wrought-iron tie-rods I. 'Ihe top K and bottom L in the structure are formed of brick arches springing from onever tical wall to the other opposite. Inthis oven vthere is a vertical middle partition, M, running from top to bottom, dividing the oven into two equal main divisions, each of which is subdivided by transverse arched walls into cham bers, called reducing-chambers.77 The chambers of the reducing-oven intercommunicate by means of fines or passages, so that the iiame or heated gases from the furnace pass iirst under the table or sole of the lower chamber, then over the said table, but under that of the upper chamber, and iinally over the upper table and out of the upper chamber. The welding-furnace is combined with the reducing-oven by means of flues N for the passage ofthe iiame or gases, and by means of receiving hoppers or channels P, through which the reduced ore is discharged from the reducing-chambers into the welding-furnace. The latter is constructed in the form -of a puddling-furnace with a reverberatory roof depressed about midway to deflect the iiame and concentrate the heat upon that portion of the hearth where the bloom is finally formed 'top with dampers, which can be raised and `shall now brieiiy refer to the manner of worktables and evenly spread over them and alprevious to its being taken out from the furnace and carried to the hammer or squeezer. It is heated by a fire at Q, from which it is separated by a bridge, preferably hollow and open at the sides, to allow fresh air to circulate through it. The chimney or stack S is divided from the top down to the upper table by means of an angular partition wall, T, whereby the dame or gases issuing from under the lower table are directed into the chamber abovei. e., under the upper table and over the under tableand are then conveyed out of the upper chamber into the chimney, whence they are allowed to escape into the open air. The chimney is furnished at the lowered by means of a chain 'and lever, It, but which, during the working of the furnace are kept more or less closed, as the operations in the apparatus throughout all its parts are generally effected under pressure greater than that of the atmosphere.

Having thus given the outlines of afurnace to which my improvements are applied, I

ing the same.

Charges of from fourteen hundred to eighteen hundred pounds of powdered coal and oie in the proportion of from twenty-two to twentyfive pounds of the former to one hundred pounds of the latter, properly mixed and prepared, are thrown through hoppers upon the lowed there to remain, undergoing occasional stirring through doors T, provided in the sides ofthe oven, until the oxide of iron, under the combined influence of great heat and the presence of carbonic-oxide gas, shall be freed of its oxygen, converting the oxygen of carbon into carbonio-acid gas, which together with other gaseous matter are forced by the blast through the chimney, leaving iron in its metallic state, but mixed with impurities or cinders. At this state of the operation the table or tables are discharged directly into the welding-furnace-that is, the mass of reduced ore is thrown through the hopper upon the hearth, and the hot air is allowed to circulate about it, while it is kept constantly stirred, so as to expose fresh surfaces to the action of the gases, direct action of the atmospherebeing all the time carefully avoided by keeping the working-door closed, otherwise the metal would be oxidized. Vhen the particles of iron, Src., are thus converted into a pasty mass of sufficient consistency, it is pushed forward on the hearth opposite the ballingdoor,where the heat is very intense, being reverberated by the depression in the roof. The particles of iron now agglutinate and become soon welded, when the ball is seized by means of tongs and conveyed to the hammer and squeezer, under the action of which the slag is pressed out and the metal consolidated.

From the above it will be seen that the temperature of the flame and gases is higher in the welding-furnace than in the reducing-oven,

and that in the reducing-oven it must necessarily and gradually decrease from the point of ingress at the ue connecting it with the furnace to the point of egress-z2 e., at the flue connecting the upper chamber with the chimney. This is a source of great inconven ience, for the reason that the ore on the several tables, not being exposed to the` same degree of heat, is in some places too highly heated, which injuriously affects the iron when reduced from the ore, while in other places it is exposed to a degree o f heat insufficient to effect the composition of the ore in the manner hereinbefore referred to. On the other hand, the temperature not being the same throughout all the chambers, it was found necessary to allow the mixture of coal and ore to remain on the table exposed to the action of the iiame and gases for a greater length of time in those chambers in which the temperature is less than in those in which it is higher, and the consequence was that the tables are necessarily discharged at irregular intervals of time, which greatly interfered with the proper working of the welding furnace, and was wasteful of fuel because of the furnace periodically receiving more charges than could be conveniently worked, and of its periodically receiving less than is necessary to lmake good use ofthe heat derived at great cost offuel. Again, the iron derived from the different charges indicated a want of uniformity of quality and texture vgreatly detrimental to this sort of manufacture. Thus one ball would be composed of tough and fibrous iron,while the other would be made of iron, brittle, and have all the characteristics of burnt iron; and, lastly, while in a certain part of the oven the p roduction of iron was 'constantly a maximum, it was invariably less in the other parts, too great heat or insufficient heat having a tendency to reduce the iron to ciuder.

The importance of my present invention will now be readily understood, its object being to equalize the temperature throughout all the chambers of a reducing-oven, and I accomplish this in three different ways:

First,I by increasing the capacity of the chambers in proportion to the intensity of the heat of the iiame passing through them. This may be effected in various ways. make the tables parallel to each other and to the top or roof of the whole oven, and to give greater height to the lower chamber than to the upper chamber-that is to say, I make the distance between the two tables greater than the distance of the sole of the upper chamber to the roof the oven. In Fig. 3 of the Vaccompanying drawings, which is a sectional view similar to that in Fig. l, the chamber U (sup- I prefer to iiues leading` to and from the chambers in accordance with the intensity of the heat of the flame passing through said flues. This is carried into effect-by making the orifice of the exit-flue smaller, and the ingress-line larger in that chamber in which it is proposed to increase for the purpose of equalizing the temperature throughout all the chambers. Thus by making in the lower chamber the ingressiiue X X smaller than its egress-line Y, and at the same time making the ingress-Hue Y to the upper chamber larger than its egress-flue Z the desired result will be obtained-that is, the two chambers will be heated uniformly-for the reason that while the flame is somewhat restrained from entering the lower chamber, yet free to issue from it, it is free to enter, but slow to issue from,the upper chamber, the effect of which under the influence of the pressure of the blast will be that thegases will emit more heat in proportion to their loss of temperature in passing frbm one chamber to the other.

Third, by so combining chambers with ilues that the capacity of the former and the area of the latter shall be proportioned to the intensity of the heat of the flame. This is the mode which I employ in preference to others to carry into ei'ect my said invention. By it a proper harmony of structure may be attained which produces the most beneficial results. Thus without effecting the object by only increasing or decreasing the capacity of the chambers, or by only increasing or decreasing the area of the flues to and from the chambers, both means may be combined, as

or may be carried into effect, I shall statemy claims as follows:

1. The method hereinbefore described of equalizing the temperature throughout all the 'chambers of the reducing-oven by increasing the capacity of said chambers in proportion to the intensity of the heat of the flame passing through them, substantially as set forth.

2. The method hereinbefore described of equalizing the temperature throughout all the chambers of the reducing-oven by proportioning the area of the iiues leading to andfrom the chambers in accordance with the intensity of the heat of the flame passing through said due and chamber, substantially as set forth.

3. The method' hereinbefore described of equalizing the temperature throughout all the chambers ofthe reducing-oven by so combining said chambers with flues that'the capacity of the'former and the area of the latter are prO- portionate to the intensity of heat of the liame, substantially as set forth.

In testimony whereof I have signed my name to this specification before two subscribing witnesses.

c JOSEPH YATES. Witnesses:

, A. PoLLoK, O. BROWN. 

